Skin Deep - Clinical & Cosmetic Dermatology Blog

Skin Deep is a blog for dermatologists and skin care professionals with focus on theoretical, cosmetic and aesthetic dermatology. We do evaluations and comparisons of cosmetic and esthetic dermatology devices, products and journal articles based on scientific rationale. This blog is associated with ‘Dermatologists Sans Borders’ one of the largest curated groups of skin care professionals on facebook. If you are looking for non-technical information, please visit http://skinhelpdesk.com

The information presented here is not intended to diagnose, treat, cure or prevent any disease. Always seek the advice of your own physician or other qualified health care professional. Read full Disclaimer.

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Friday, April 18, 2014

Ductal hypoxia in acne: the missing link between comedogenesis and inflammation

Vol. 201, Issue 5: etoc 1
Vol. 201, Issue 5: etoc 1 (Photo credit: TheJCB)
This study proposes hypoxia inducible factor (HIF1) as the missing link between the androgenic and inflammatory theories of acne pathogenesis. Androgenic hormones  induce intraductal keratinocyte proliferation resulting in ductal hypoxia. Hypoxia induces the failure of both terminal differentiation and desquamation thus inducing the non inflammatory form of acne. Later it stimulates the production of HIF-1, and the HIF-1 stimulates inflammatory cytokines (thus inducing the inflammatory form of acne). P.Acnes is seen more as an effect than the cause of acne since the facultative anaerobe thrives in this hypoxic environment, thereby acting as a serendipitous marker of acne.

Interesting and plausible theory, but with doubtful clinical utility.

Do you have an acne problem? Consult SkinHelpDesk.com

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Sunday, March 30, 2014

The Naranjo algorithm

English: A hand scratching at a pruritus on arm
A hand scratching at a pruritus on arm (Photo credit: Wikipedia)
For decades, retinoic acid (RA) is known as the most potent therapeutic option in the therapy of acne. A recent study (1) suggests inhibition of endogenous RA metabolism and amplification of endogenous RA signalling as a mechanism underlying the biochemical actions of antibiotics such as tetracycline and erythromycin in acne therapy. So, at the fundamental molecular level, the mechanism of action of these disparate agents converge.

The mechanism of pruritus in Dandruff/seborrhoeic dermatitis (D/SD) is not well understood. Histamine is one of the biomarkers of pruritus now widely used in treatment efficacy trials. The exact mechanism leading to histamine release and pruritus is not yet clear. This study (2) demonstrated significant increase in cathepsin S in D/SD and recommends it as a potential marker of pruritus in D/SD and in assessing the effect of anti-dandruff treatments.

Recently I came across The Naranjo algorithm, Naranjo Scale, or Naranjo Nomogram, a questionnaire designed by Naranjo et al. for determining the likelihood of whether an ADR (adverse drug reaction) is actually due to the drug rather than the result of other factors (3). Probability is assigned via a score termed definite, probable, possible or doubtful. Dermatologists are usually consulted whenever there is a suspected ADR, but I never knew about this methodology till now.

Itching
Itching (Photo credit: amareta kelly)
References:

1. Hellmann-Regen, J., Herzog, I., Fischer, N., Heuser, I. and Regen, F. (2014), Do tetracyclines and erythromycin exert anti-acne effects by inhibition of P450-mediated degradation of retinoic acid?. Experimental Dermatology, 23: 290–293. doi: 10.1111/exd.12358

2. Viodé, C., Lejeune, O., Turlier, V., Rouquier, A., Casas, C., Mengeaud, V., Redoulès, D. and Schmitt, A.-M. (2014), Cathepsin S, a new pruritus biomarker in clinical dandruff/seborrhoeic dermatitis evaluation. Experimental Dermatology, 23: 274–275. doi: 10.1111/exd.12357

3. http://en.wikipedia.org/wiki/Naranjo_algorithm

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Monday, February 17, 2014

Photo Finish

English: Skin layers
English: Skin layers (Photo credit: Wikipedia)
Sorry for going back to the skin imaging theme once again. During Dicoderm discussion, we discussed about the growing importance of photodiagnosis (diagnosing dermatological condition from an image, without actually seeing the patient). We realised that we may be good at recognizing large and complex patterns but we may be poor at quantifying and assessing the subtle differences. This makes photodiagnosis a difficult skill to master and it may be different from clinical diagnosis in-vivo. In photodiagnosis large and complex patterns are often hidden, with subtle color difference cues available in abundance. An organized crowdsourcing platform for photo-diagnosing is taking shape here in dermgrandrounds. But I will blog about it in detail later.

When I explored the color space for skin tone assessment (CHARM), I considered the possibility of some diagnostic information being hidden in the color space matrix. I even discussed it with few of my friends ( SK and +Feroze Kaliyadan ). (BTW All the best SK with your new baby IDS, I just saw the website when I googled your name). I wanted to subject the data to some machine learning algorithm such as a tree classifier or SVM. But I didn’t have enough data.

Korean scientists from the Seoul National University College of Medicine and Seoul National University Bundang Hospital, have done just that. A decision tree with enough specificity to differentiate erythrotelangiectatic rosacea,  papulopustular rosacea and seborrheic dermatitis has been published in BJD recently (1) (Print version may not be out yet). A full five peels to this research. (OK, I am biased :) Hopefully the research team will someday see my CHARM!

Here is a short but useful review on selective hair therapy.(2) The authors argue that novel technologies that could improve guidance into hair follicles (= higher selectivity, sparing of unaffected tissue), retention (= reduced application frequencies, increased and prolonged exposure to the drug) and protection from degradation in the skin environment is already available. But they are yet to become effective products. Are we obsessed with Amanda’s Apple?

1. Characteristics of subjective recognition and computer-aided image analysis of facial erythematous skin diseases: A cornerstone of automated diagnosis. Choi, J W;  Kim, B R; Lee, H S; Youn, S W (2013) The British journal of dermatology [Pubmed]

2. Selective hair therapy: bringing science to the fiction. Vogt, Annika; Blume-Peytavi, Ulrike (2014) Experimental dermatology. vol. 23(2) p. 83-6 [Pubmed]

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Saturday, January 18, 2014

Sonography and Microscopic MRI of Skin

Magnetic resonance imaging (MRI) series of a h...
Magnetic resonance imaging (MRI) series of a human head (Photo credit: Wikipedia)
Dermatology Image Tagger Version 2.0 is released. (Download here) This version introduces encryption for all tags except date. It reduces the speed of search, but will be more secure. Why am I so paranoid about patient privacy when you see patient photographs being posted all the time in some facebook groups? Here is the reason.(Dermatology Clinic Hit With $150,000 HIPAA Penalty)

In the DICODerm initiative we are trying to adapt the radiology image management tools to dermatology. Recently I came across two articles, that could introduce another dimension to this patronage. One dealt with the Sonography of Acne Vulgaris.(1) The authors conclude ”facial acne vulgaris often involves deeper tissues, beyond the reach of the spatially restricted clinical examination”. However it is important to demonstrate at most the clinical utility of it in the management of acne vulgaris. I feel there is a risk of channeling medically essential services to less critical situation especially in resource deprived areas.

Another article introduces a dynamic new concept of “Microscopic MRI of skin”.(2) Though it is still early times, this could well develop as a “non-invasive” skin biopsy technique, with potential for a huge clinical impact. Hope Dr Laistler and his team can convert their HTS coil into a useful tool in a dermatologist’s armamentarium.

References:
(1) Wortsman, Ximena et al. "Sonography of Acne Vulgaris." Journal of Ultrasound in Medicine 33.1 (2014): 93-102.
(2) Laistler, Elmar et al. "In vivo MR imaging of the human skin at subnanoliter resolution using a superconducting surface coil at 1.5 tesla." Journal of Magnetic Resonance Imaging (2013).

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Wednesday, December 18, 2013

The Loyalty of Anatomy

nerves of left upper extremity
nerves of left upper extremity (Photo credit: Wikipedia)
The medical knowledge is never static. Most of the drugs we prescribe today were not even there few years back. Personalized medicine is just around the corner, though he is taking a lot of time to come out of the corner. Many theories have been shattered and new ones made. As I posted last week, the mitotic activity of the good old basal cells is highly suspicious!

Though I never trusted the loyalty of physiology or pharmacology, I used to respect anatomy. Ulnar nerve has remained ulnar nerve over the years. It still remains medial to the triceps tendon and will remain so for ever. So for me anatomy was loyal and reliable. Unfortunately not any more.

In the initial days of my PG, in the first few pages of Moschella, I read about the superficial and deep vascular plexus of the skin. Like most things in anatomy, I believed it without actually seeing it. I trusted Moschella to have seen it all. But this article(1) make me doubt the loyalty of anatomy in general and also suspect everything in dermatology that I have not seen with my own eyes!

1. Geyer, SH. "The dermal arteries of the human thumb pad." 2013. 

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Sunday, December 15, 2013

5 things Dermatologists should not do

DNA
DNA (Photo credit: Steven2005)
What happens when the DNA replicates without cellular replication. It leads to formation of ‘polyploid’ cells. Though polyploidy has been noted in megakaryocytes, bone marrow, myocardiocytes and hepatocytes, it has not been described much in skin. A new study proposes that basal keratinocytes may show up to 50% polyploidization, though its functional relevance is not yet known. 

AAD followed the footsteps of 42 other specialties and published a list of ‘5 things Dermatologists should not do’ along with the commentary from Dr. Goldenberg.

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Sunday, December 08, 2013

Evaluating Industry Attractiveness of Cosmetic Dermatology: an India & Middle East perspective.

Westlake Dermatology Prep Oval 003
Westlake Dermatology Prep Oval 003 (Photo credit: Associated Fabrication)
DICODerm is gathering steam. Thanks for all the contributions from +Apratim Goel, +Feroze Kaliyadan+Geraldine Jain and +Sunaina Hameed. Special thanks to +Feroze Kaliyadan for the contributions on positioning standards. Will work on it some more and get some technical expert to have a look. I was actually planning to write several posts on #DICODerm, but most of the issues I wanted to highlight have already been discussed. So I am starting yet another interesting (probably a little controversial) topic:

If you attend a dermatology conference in India or Middle East, there is a very high probability that you will be surrounded by dermatologist-CEOs (If you are not one yourself). I don’t think you will find that many CEOs in any other specialty. The dermatologist-CEOs have added a unique dimension to the cosmetic dermatology industry and have ended the era of brand monopoly. Can all these dermatologist-CEOs make it big? Unlikely, as in any other business. Can the corporate brands strike back? Depends, on their strategic capabilities.

I am not an MBA, but for the last few months I am surrounded by business minds and I am extending few lessons I have learnt from them to write this series.

My motive is rather selfish. I am just trying to learn how to apply business principles in real world situations in health care. But it may help budding dermatologist entrepreneurs to position their business better. This may also help consumers to make informed decisions too. For a start: Should you, as a consumer consider having your BOTOX® in a brand or an individual clinic? We shall try to answer questions like this in due course.

I shall use the popular Porter five forces analysis:

Illustration of Porters 5 Forces. Illustrates ...
Illustration of Porters 5 Forces. Illustrates article Porter 5 forces analysis (currently available in 11 languages). (Photo credit: Wikipedia)

  • Threat of new entrants
  • Threat of substitute products or services
  • Bargaining power of customers
  • Bargaining power of suppliers
  • Intensity of competitive rivalry


Here are my satirical views on the cosmetic dermatology industry and my white paper on research methodologies in cosmetic dermatology.

What are your views on the cosmetic dermatology market based on the above five forces?

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